Ansys Learning Forum › Forums › Discuss Simulation › Photonics › RCWA results different from FDTD › Reply To: RCWA results different from FDTD
Hi Areum,Â
I believe the a k-vector value of 15 is not going to be enough. What is the maximum number of k-vectors you have used so far? Usually, we ask customers to perform convergence testing i. e. keep increasing the k-vector as until the results converge. If on increasing the number of k-vectors, you see changes in the spectrum that most likely means that the k-vector value is not high enough. Does the geometry have same periodicity in the transverse directions? Also, is there a large index contrast between the geometry and the surrounding? If that is the case, I will ask you to use the tangent vector field method.
Regards,
Amrita